1. Field of the Invention
The present invention relates to a process for the preparation of 2,2-difluoroethylamine starting from 2,2-difluoro-1-chloroethane.
2. Description of Related Art
The compound 2,2-difluoroethylamine is an important intermediate in the preparation of active substances. Various methods for the preparation of 2,2-difluoroethylamine are known (e.g., Schwartz et al., Chem. Zentralblatt, Volume 75, 1904, pages 944-945; Dickey et al., Industrial and Engineering Chemistry, 1956, No. 2, 209-213). The known processes are disadvantageous since they either have a very long reaction time with only a low yield or because the reaction mixtures are highly corrosive, for which reason the known processes are unsuitable for commercial-scale use.
Starting from the known processes for the preparation of 2,2-difluoroethylamine, the question now arises of how 2,2-difluoroethylamine can be prepared in a simple and inexpensive way. The inventors have found that 2,2-difluoroethylamine can be prepared particularly advantageously if an imide intermediate is first prepared and then cleaved.